Question

simplify the expression: (5x+1/5)^2

Answer 1

Have you done the "FOIL" (first, outer, inner, last) method?

Answer 2

i just learned today but i'm confused

Answer 3

Ok, you write the expression like:
(5x + 1/5) (5x + 1/5)

Then multiply the two FIRST terms together... (5x)(5x) = 25x^2
multiply the two OUTER terms together (the first and last terms): (5x)(1/5) = x

then multiply the middle or INNER terms: (1/5)(5x) = x

Then multiply the two LAST terms (1/5)(1/5) = (1/25)

and add it all up

Answer 4

(5x + 1/5)(5x + 1/5)

25x^2 + x + x + (1/25)

then simplify:
25x^2 + 2x + (1/25)
\[25^{2}+2x+\frac{ 1 }{ 25 }\]

Answer 5

i understand now ^.^ thanks!

Answer 6

Squaring something that has two parts like (a+b) is just multiplying (a+b)(a+b)

and the FOIL approach just helps you make sure you distribute everything properly across the parenthesis when you multiply.

you already know that a(a+b) would be a^2 + ab because of distribution
and b(a+b) would be ab + b^2 the same way

Answer 7

Great :) Glad to help!